Glossary of Oceanography Midterm 1

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An interdisciplinary study of the relationship between geological, biological, chemical, physical, and management processes in the sea.

Inner Planets

Mars, Mercury, Earth, Venus. Also called Telluric Planets. Consist of heavy material and have high boiling and melting temperatures.

Earth is unique because it has an ozone layer, water, and life.

Outer Planets

Saturn, Jupiter, Uranus, and Neptune. Also called Cold Giants. Made of lighter elements and have low melting and boiling temperatures.

Big Bang Theory

15 billion years ago a shock wave from an exploding star caused spinning gravitational attraction around a single point smaller than an atom. The gravitational attraction increased more and more matter until, eventually, the sun and planets formed.

Big Bang Evidence (2 Parts)

Theory of Relativity (Albert Einstein)- says universe is either expanding or contracting

Doppler Effect (Edwin Hubble)- discovered that the universe is expanding

Primordial Soup Theory

Hydrogen, ammonia, methane, and water combined with a catalyst in the ocean to form amino acids which would have been able to combine to create organic material which eventually gave rise to life. Catalysts: electrical discharge, ultraviolet light, geothermal and hydrothermal heat from the ocean floor

Why is water ideal for life?

It retains heatIt moderates temperatureIts a solvent and dissolves many chemicalsAnd it transports nutrients

Definition of Life

Must be able to grow more complexObtain and use energyand Reproduce

First organism

Archea

Primordial Pizza Theory

Same as primordial soup theory but states that this reaction took place on land (a solid surface), because the elements were not sufficient enough to come together with out being torn apart in the ocean.

Panspermia Theory

Suggests that life seeds came from outer space on ice comets and planets exchanged life

Which is the most accepted hypothesis for the origin of life?

Primordial Soup

Which theory of the origin of life has the most funding for further study?

Panspermia Theory

Formation of earth's water sources

3.7 billion years ago earth's surface cooled enough for water to exist primarily as a liquidoutgassing: gases released from volcanic vents, remains as water vapor to create clouds and eventually rainComets: tiny ice comets collided with earth and melted providing water

Formation of Atmosphere

3.5-4.5 billion years ago- Carbon Dioxide combined with Water and forms glucose and oxygen for primary production- the oxygen rose up and formed the ozone layer.

Stages of Ocean Exploration

Setting Out (till 100a.d.)Expanding provincial realms (100-1400a.d.)Age of Discovery (1400s-1700s)Charting the World (1700-1900s)Twentieth Century and Beyond

Characteristics of Setting Out

Used oceans primarily for food- vessels propelled by oarsGreeks used the North Star to measure latitudePtolemy's map- produced a map of the roman world including latitude and longitude lines Aristotle- calculated circumference of the earth, father of oceanography

Characteristics of Expanding Provincial Realms

Vikings did not record anything so we are not able to replicate their ship making skills- but colonized Iceland, Greenland, and NewfoundlandChinese discovered the compass and used multi-massed shipspassed this info on to arabs to store in alexandria library

HMS Challenger

A 4 year expedition- Captain John Murray- identified almost 5000 new species of marine life, found life existed deep in the ocean, mapped the ocean floor by measuring depth, recorded water temperatures, salinity, and currents, and collected sediment samples from the ocean floor

Characteristics of Charting the World

Two important Expeditions:The Beagle- charles darwin + origin of species- purpose of expedition was to complete a survey of parts of South AmericaHMS Challenger- inspired by Darwins work- Captain John Murray- father of Modern OceanographySCUBA- Jacques Cousteau and Emile Gagnan develop modern SCUBA

Age of Discovery Characteristics

Voyaging for God, Glory, and GOldEurope discovered Alexandria Library during the crusades- caught up to the rest of the worldColumbus- first european to reach caribbeanPortugal developed south route- sailed around africa to the west indies

proposed the theory of continental drift and hypothesized that all of the present-day continents were once part of a single supercontinent named Pangaea- wasn't accepted because he couldn't describe how the continents split

Evidence of continental split

Found geological, biological, and meteorological evidence

fit of the continntsthe distribution of fossilsa similar sequence of rocks at numerous locationAncient climatesapparent wandering of the Earth's polar regions

Pangaea

The one supercontinent before the continental split

Ocean Data Collected in the 1950s

It was a worldwide effort to lay down telecommunication cables

Temperature readings- in areas of high mountain readings the temperature was very highSediment analysis with radiometric dating- found newer sediment closer to ridgesAreas with high sysmic activity- found areas with lines of sysmic activity

were then able to map the 7 major plates and the 21 minor plates and form the Plate Tectonics theory

Line of volcanoes that circles most of the pacific ocean- known as the ring of fire because it is the site of frequent volcanic eruptions

Sea-Floor Spreading

The creation of new oceanic crust at mid-ocean ridges and movement of the crust away from mid-ocean ridges

Abyssal

Greek- means "without bottom"Very little lifeWater has not been mixed since its so deep

Mid-oceanic ridges

Mountain range that surrounds the earthMost common feature of the ocean

Formation of hydrothermal vents

Form on ridgesCold water moves down the cracks in the ridge and becomes superheated from the ridge heat sourcerises back up through vents carrying dissolved minerals and gases10-20 degrees warmer than normal ocean floor bottomLIFE IS ABUNDANT

Ocean Trench

Arch Shaped depressions that occur where two plates convergeGeologically active- large earthquakesColdest water temperaturesdeepest place in Earth's crust

Characteristics of Abyssal Plains

flat, deep sediment covered floor of the oceanexist between ridges and inactive margins of the continentsediment has mostly a terrestrial or shallow-water origin

large and steep submerged inactive volcanoes- form in groups near spreading centers- very common in the pacific

Arc Islands

Chain of volcanic islands that parallel trenches

Aleutian Islands, Lesser Antilles, Mariana Islands

Volcanic Island

Form from a stationary hot spot that shoots up lava and produces an islandPlate continues to move and then hot spot shoots up another island

Hawaii

Eustatic Sea Level

Change that has happened throughout geological time due to plate tectonics and climate change

Local Sea Level

Short term changes on sea level

Oceanic vs. Continental Crust

Oceanic Crust is made of BasaltContinental Crust is made of Granite

Basalt is DENSER than Granite

Turbidity Currents

mixtures of sediment and sea water that are denser than pure sea water and so flow down the continental slopecan do so at tens of kilometers per hourcan be slow and steady or large catastrophic events triggered by an earthquake

1. the crust- thin layer of solid rock, all the features you see around us2. The Mantle- below the crust is a hot, partly molten layer- made up of thick heavy material3. The outer core- molten mass of mostly iron with some nickel- extremely hot- material flows because its so hot4. Inner Core- large ball of iron and nickel- hottest layer, but it is solid because its crushed under he enormous weight of the outer core and the mantle

The two ocean processes that modify secondary coastlines are ________ and _____.

chemical weatheringphysical erosion

Primary Coasts

Coasts dominated by land processesErosion- formed during low sea level and are now flooded- Chesapeake bayDepositional- coasts that deposit more material than is removed by marine processes- River DeltasVolcanic- Formed from lava flows (Hawaii)Fault- vertical fault movement along a coast can cause land to uplift or subside- horizontal fault movement can cause the opening of a ulf or a linear shoreline

difference between chemically weathered and physically weathered

chemically weathered the rock is dissolved

physically weathered the rock is abraded

Features of a Secondary Coastline

Sea Cliff- precipitous slope caused by collapse of wave cut notchesWave-Cut Platform- flat platform caused by underwater erosion of bedrockSea Cave- cave cut waves at a zone of weakness in the sea cliffHeadland- protrusion in the coastline of more resistant rockSea Arch- two caves on opposite sides of a headland joinSea Stack- A pillar of rock just off a headland formed by the collapse of a sea arch

Longshore Current

moves sediment along the shoreline in a certain direction- caused by the slight angle of the waves on the shoreline

usually doesn't change

Coastal Cells

sector of the coastline where input of land sediment = outflow of sediments onto the continental shelf or submarine canyons

Sand Spit

finger of sand that extends out into the entrance to a bay- forms in the direction of the longshore current and is deposited as the current looses velocity in the bay

curled tip caused by refraction of waves

Bay Mouth Bar

a sand spit that fully closes off the entrance to a bay

Inlet

a break in the bay mouth bar caused by tidal action

barrier island

exposed sandbars that run parallel to the coast- they are thought to be submerged dunes of a lower sea level

moving islands- migrating both toward the shore and parallel to the longshore current- often flooded during winter storms

lagoon

the shallow body of seawater between the barrier island and the shore

Longshore bar

where sediment from the longshore trough is deposited just seaward of the trough

Summer vs. Winter profiles

Summer- have gentle beach slope and a sand bar

Winter- steep slpe and no sand bar

Sand on the dunes replenish sand on the beach in the summers- sand gets fixed on the dunes with plants

Biologically Modified Coasts

Coastlines modified by living organisms- like coral reefs and mangrove trees in tropical areas and salt marsh plants in temperate areas